Description
A weakness has been identified in mruby 3.4.0. This vulnerability affects the function ary_fill_exec of the file mrbgems/mruby-array-ext/src/array.c. Executing a manipulation of the argument start/length can lead to out-of-bounds write. The attack needs to be launched locally. The exploit has been made available to the public and could be used for attacks. This patch is called 93619f06dd378db6766666b30c08978311c7ec94. It is best practice to apply a patch to resolve this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | mruby | 3.4.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | mruby | No fix yet | — |
| Ubuntu 26.04 LTS | mruby | No fix yet | — |
| Ubuntu 25.10 | mruby | No fix yet | — |
| Ubuntu 24.04 LTS | mruby | No fix yet | — |
| Ubuntu 22.04 LTS | mruby | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | mruby | No fix yet | — |
| Ubuntu 18.04 LTS | mruby | No fix yet | — |
| Ubuntu 16.04 LTS | mruby | No fix yet | — |
Advisories 1
- WID-SEC-2025-2563 Microsoft Azure Linux: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 11, 2026
References
- VDB-331511 | mruby array.c ary_fill_exec out-of-bounds write vdb-entry technical-description
- VDB-331511 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #680879 | mruby 3.4.0 Out-of-bounds Write third-party-advisory
- https://github.com/mruby/mruby/issues/6650 issue-tracking
- https://github.com/mruby/mruby/issues/6650#event-20443453808 issue-tracking
- https://github.com/mruby/mruby/issues/6650#issuecomment-3430851605 exploit issue-tracking
- https://github.com/makesoftwaresafe/mruby/commit/93619f06dd378db6766666b30c08978311c7ec94 patch
- https://github.com/mruby/mruby/ product